English

Endomorphisms of projective varieties

Algebraic Geometry 2007-06-22 v2

Abstract

We study complex projective manifolds X that admit surjective endomorphisms f:X->X of degree at least two. In case f is etale, we prove structure theorems that describe X. In particular, a rather detailed description is given if X is a uniruled threefold. As to the ramified case, we first prove a general theorem stating that the vector bundle associated to a Galois covering of projective manifolds is ample (resp. nef) under very mild conditions. This is applied to the study of ramified endomorphisms of Fano manifolds with second Betti number one. It is conjectured that the projective space is the only Fano manifold admitting admitting an endomorphism of degree d>1, and we prove that in several cases. A part of the argumentation is based on a new characterization of the projective space as the only manifold that admits an ample subsheaf in its tangent bundle.

Keywords

Cite

@article{arxiv.0705.4602,
  title  = {Endomorphisms of projective varieties},
  author = {Marian Aprodu and Stefan Kebekus and Thomas Peternell},
  journal= {arXiv preprint arXiv:0705.4602},
  year   = {2007}
}
R2 v1 2026-06-21T08:33:47.827Z